Sunday's fixture saw the capital club extend their unbeaten run this term to 15 games, with Cavani and Ibrahimovic leading the way.
The former, who joined from Napoli in the close-season, opened the scoring with a header before earning a penalty that his Swedish partner fired home.
Thiago Silva then got in on the action prior to Ibrahimovic finding the net again from the spot.
"Having Cavani makes my game easier," Ibrahimovic told L'Equipe. "We help each other. If I do not score, he's scoring.
"This is something we did not have last year. He also does a lot of defensive work and that is good for the team. This is what we needed.
"We're stronger this year. If we continue using Cavani the right way, it can be good for the team."
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